具有嵌套有效负载的JSON绑定

Question

I'm using Go and Buffalo to develop an API. When receiving a request, it is possible to automatically map the JSON payload to a struct:

func MyAction(c buffalo.Context) error {
  u := &User{}
  if err := c.Bind(u); err != nil {
    return err
  }
  u.Name // "Ringo"
  u.Email // "[e-mail]"
} 

However, it supposes that the payload is of this shape:

{
  "name": "Ringo",
  "email": "[e-mail]"
}

If for some reason, the incoming payload has a key:

{
 "user": {
    "name": "Ringo",
    "email": "[e-mail]"
  } 
}

The binding won't work. I couldn't find how to handle this case. How should I approach this ?

Answer 1

Perhaps you can wrap your struct with map[string]User{}, here is an example:

func MyAction(c buffalo.Context) error {
  u := map[string]User{
    "user": User{},
  }
  if err := c.Bind(&u); err != nil {
    return err
  }
  user := u["user"]
  user.Name // "Ringo"
  user.Email // "[e-mail]"
} 

In my opinion define a struct would be cleaner solution:

type UserObject struct {
    User struct {
        Email string
        Name  string
    }
}

func MyAction(c buffalo.Context) error {
   u := UserObject{}
   if err := c.Bind(&u); err != nil {
      return err
   }
   user := u.User
   user.Name // "Ringo"
   user.Email // "[e-mail]"
}